The terms yohimbine, yohimbine hydrochloride, and yohimbe bark extract are related but different. Yohimbine is an active chemical (indole alkaloid) found in the bark of the Pausinystalia yohimbe tree. Yohimbine hydrochloride is a standardized form of yohimbine that is available as a prescription drug in the United States. Research has shown it to be effective in the treatment of male impotence. Yohimbine hydrochloride has also been used for the treatment of sexual side effects caused by some antidepressants (SSRIs), as a blood pressure boosting agent, for dry mouth, and for nervous system dysfunction.

In general, there is a lack of research on yohimbe bark extract, which generally contains low concentrations of yohimbine (6% indole alkaloids, of which only 10-15% is yohimbine). Therefore it is unknown if commercial preparations share the same effects of yohimbine hydrochloride.

These uses have been tested in humans or animals. Safety and effectiveness have not always been proven. Some of these conditions are potentially serious, and should be evaluated by a qualified healthcare provider.

GRADE *

Research on the effects of yohimbine in anxiety has shown mixed results. Further research is needed to draw conclusions.

C

Historically, yohimbe has been used for body building and enhancing athletic performance. Due to stimulant effects, it has been thought that yohimbe may enhance exercise performance, increase fat loss, and increase muscle mass. Limited research showed a lack of effect of yohimbe on total body mass or body muscle mass, but a decrease in fat mass among athletes. Further study is needed before a conclusion can be made.

C

Early evidence suggests that yohimbine in combination with an antidepressant may improve symptoms of depression. Research of yohimbine alone showed a lack of benefit in major depressive disorder. More research is needed before a firm conclusion can be made.

C

Limited evidence reports that yohimbine may increase saliva production and help with dry mouth. More research is needed before a strong conclusion can be made.

C

Yohimbine hydrochloride is a prescription drug that has supporting evidence in treating male impotence. Although yohimbine is present in yohimbe bark extract, levels are variable and often very low. Therefore, although yohimbe bark has been used traditionally to reduce male erectile dysfunction, sufficient scientific evidence is lacking to form a firm conclusion in this area. Further research is needed.

C

It is theorized that yohimbine may improve orthostatic hypotension (lowering of blood pressure when standing up) or other symptoms of autonomic nervous system dysfunction. However, yohimbe bark extract may not contain significant amounts of yohimbine, and therefore may lack these proposed effects. More research is needed before a strong recommendation can be made.

C

Limited evidence suggested yohimbine hydrochloride as a potential agent to improve orgasmic dysfunction. More well designed studies are needed before a conclusion can be made.

C

Evidence supporting yohimbine use for orthosthatic hypotension, or low blood pressure upon standing up, is mixed. Further study is needed.

C

Yohimbine hydrochloride, a standardized form of yohimbine that is available as a prescription drug in the United States, has been suggested to treat sexual dysfunction due to SSRI antidepressants. However, research in this area is limited, and more study is needed before a recommendation can be made.

C

* Key to grades

A: Strong scientific evidence for this useB: Good scientific evidence for this useC: Unclear scientific evidence for this useD: Fair scientific evidence for this use (it may not work)F: Strong scientific evidence against this use (it likley does not work)

Tradition / Theory
The below uses are based on tradition, scientific theories, or limited research. They often have not been thoroughly tested in humans, and safety and effectiveness have not always been proven. Some of these conditions are potentially serious, and should be evaluated by a qualified healthcare provider. There may be other proposed uses that are not listed below.

Doses are based on those most commonly used in available trials for pharmaceutical standardized yohimbine hydrochloride. Available clinical studies are lacking for administration of over-the-counter yohimbe.

A tea can be prepared by simmering 5-10 teaspoons of shaved yohimbe bark in 1 pint of water (with a further suggestion of adding 0.5-1.0 grams of vitamin C to the tea). Safety and efficacy data are lacking for this preparation.

For anxiety, 10-20 milligrams of yohimbine has been taken by mouth once or once weekly by mouth 30-60 minutes prior to undergoing virtual reality exposure, fear conditioning, or claustrophobia extinction therapy for up to four weeks.

For athletic performance, 20 milligrams of yohimbine has been taken by mouth twice daily for 21 days.

For depression, 5-30 milligrams yohimbine has been taken by mouth 3-4 times daily for ten days.

For erectile dysfunction, 5-100 milligrams of yohimbine has been taken by mouth daily in 1-4 divided doses for 2-8 weeks.

For orgasm improvement in men, 20 milligrams of yohimbine has been taken by mouth with gradual increases up to 50 milligrams.

For orthostatic hypotension, 5.4-12 milligrams of yohimbine has been taken by mouth daily for up to six months.

For sexual dysfunction due to antidepressant drugs, 15 to18 milligrams of yohimbine have been taken by mouth daily in divided doses two to four hours before sexual activity for at least three weeks.

For dry mouth, 6 milligrams of yohimbine has been taken by mouth three times daily for five days.

Children (under 18 years old)

Yohimbe and yohimbine hydrochloride are not recommended for use in children. Deaths have been reported in secondary sources.

Safety
The U.S. Food and Drug Administration does not strictly regulate herbs and supplements. There is no guarantee of strength, purity or safety of products, and effects may vary. You should always read product labels. If you have a medical condition, or are taking other drugs, herbs, or supplements, you should speak with a qualified healthcare provider before starting a new therapy. Consult a healthcare provider immediately if you experience side effects.

Allergies

Avoid in people with known allergies or sensitivities to yohimbe, any of its parts, yohimbine-containing products, or to members of its plant family.

Side Effects and Warnings

Yohimbine is generally well tolerated in recommended doses taken by healthy adults under the supervision of a qualified healthcare professional. Daily doses of yohimbine in clinical trials have ranged from 5-100 milligrams for 2-8 weeks.

Yohimbine may increase the risk of bleeding. Caution is advised in people with bleeding disorders or taking drugs that may increase the risk of bleeding. Dosing adjustments may be necessary.

Yohimbine may alter blood pressure. Caution is advised in people taking drugs or herbs and supplements that lower blood pressure.

Yohimbine lacked an effect on blood sugar levels, but was reported to increase effects of diabetic medications. Caution is advised in people with diabetes or hypoglycemia, and in those taking drugs, herbs, or supplements that affect blood sugar. Blood glucose levels may need to be monitored by a qualified healthcare professional, including a pharmacist, and medication adjustments may be necessary.

Multiple interactions have been suggested with yohimbine hydrochloride, which may also apply to yohimbe bark extract, which contains variable (albeit low) amounts of yohimbine alkaloid.

Yohimbe may increase the risk of bleeding when taken with drugs that increase the risk of bleeding. Some examples include aspirin, anticoagulants ("blood thinners") such as warfarin (Coumadin®) or heparin, anti-platelet drugs such as clopidogrel (Plavix®), and non-steroidal anti-inflammatory drugs such as ibuprofen (Motrin®, Advil®) or naproxen (Naprosyn®, Aleve®).

Yohimbe may increase effects of diabetic medications. Caution is advised when using medications that may also lower blood sugar. People taking drugs for diabetes by mouth or insulin should be monitored closely by a qualified healthcare professional, including a pharmacist. Medication adjustments may be necessary.

Yohimbe may alter blood pressure. Caution is advised in people taking drugs that lower blood pressure.

Yohimbe may interfere with the way the body processes certain drugs using the liver's "cytochrome P450" enzyme system. As a result, the levels of these drugs may be altered in the blood, and may cause altered effects or potentially serious adverse reactions. People using any medications should check the package insert, and speak with a qualified healthcare professional, including a pharmacist, about possible interactions.

Multiple interactions have been suggested with yohimbine hydrochloride, which may also apply to yohimbe bark extract, which contains variable (albeit low) amounts of yohimbine alkaloid.

Yohimbe may increase the risk of bleeding when taken with herbs and supplements that are believed to increase the risk of bleeding. Multiple cases of bleeding have been reported with the use of Ginkgo biloba, and fewer cases with garlic and saw palmetto. Numerous other agents may theoretically increase the risk of bleeding, although this has not been proven in most cases.

Yohimbe may increase effects of herbs or supplements that affect blood sugar. Caution is advised when using herbs or supplements that may also lower blood sugar. Blood glucose levels may require monitoring, and doses may need adjustment.

Yohimbe may cause alter blood pressure. Caution is advised in people taking herbs or supplements that lower blood pressure.

Yohimbe may interfere with the way the body processes certain herbs or supplements using the liver's "cytochrome P450" enzyme system. As a result, the levels of other herbs or supplements may become altered in the blood. It may also alter the effects that other herbs or supplements possibly have on the P450 system.

Soeter M and Kindt M. Stimulation of the noradrenergic system during memory formation impairs extinction learning but not the disruption of reconsolidation. Neuropsychopharmacology 2012;37(5):1204-1215.

The information in this monograph is intended for informational purposes only, and is meant to help users better understand health concerns. Information is based on review of scientific research data, historical practice patterns, and clinical experience. This information should not be interpreted as specific medical advice. Users should consult with a qualified healthcare provider for specific questions regarding therapies, diagnosis and/or health conditions, prior to making therapeutic decisions.